Anthracene dye.



UNTTED STATES Patented August 9, 1904.

PATENT OFFICE.

RENE BOHN, OF MANNHEIM, GERMANY, ASSIGNOR TO THE BADISOHE ANILIN & SODA FABRIK, OF LUDWIGSHAFEN-ON-THE-RHINE, GER- MANY, A CORPORATION OF BADEN.

ANTHRACENE DYE.

SPECIFICATION forming part of Letters Patent No. 767,259, dated August 9 1904,

Application filed April 29, 1904. Serial No. 205,586. (No specimens.)

To all whom it may concern.-

Be it known that I, RENE BOI-IN, doctor of philosophy and chemist, a citizen of the Swiss Republic, residing at Mannheim, in the Grand Duchy of Baden, German Empire, have invented new and useful Improvements in Anthracene Dyes, of which the following is a' under the names indanthrene and flavan-' threne and can only be used for dyeing and printing when a special process is employed.

I have now discovered that by melting diamido-anthraquinon bodies with caustic potash coloring-matters can be' obtained which have bluish-gray to reddish-gray shades and which can be employed for dyeing and printing by means of the same special process. The diamido-anthraquinon bodies which I have up to the present found to answer are the 1.5, 1.8, 1.3, 2.6, and 2.7 diamido-anthraquinons and also their sulfo-acids.

The coloring-matters obtained from the diamido-anthraquinon sulfo-acids are when dry brownish-black powders and possess the same general characteristics as do the coloringmat-ters obtainable from the unsulfonated diamido-anthraquinons. They all possess (with the exception of their shades) similar properties to indanthrene and probably belong to the same class of chemical compounds. In particular they possess the same extraordinary degree of fastness, which exceeds that of all other classes of coloring-matters.

The following examples will serve to further illustrate the nature of my invention, which, however, is not limited to these examples. The parts are by weight.

Example 1: Melt three hundred (300) parts of caustic potash and while at a temperature of about one hundred and eighty degrees centigrade (180 O.) introduce slowly one hun- I dred (100) parts of 1.5-diamido-anthraquinon. After the addition heat for one (1) hour at a temperature of from one hundred and ninety to two hundred degrees centigrade (190 200 O.) and pour into water and boil and filter. The other diamido anthraquinons, either singly or in admixture with one another, can be treated in a similar manner.

Example 2: Melt three hundred and fifty (350) parts of caustic potash and while at a temperature of about one hundred and seventy degrees centigrade (170 O.) introduce slowly, while stirring, one hundred (100) parts of the sodium salt of 1.5 diamido anthraquinon sulfo acid. During the addition the melt froths up. When the frothing is finished, heat for another hour and a half (1%) at a temperature of from one hundred and ninety-five to two hundred degrees centigrade, (195 200 (1,) introduce the melt into water, boil, filter, and wash the precipitate. If instead of the sulfo-acid used in this example sulfoacids of other diamido-anthraquinons be employed, the method of procedure remains the same.

The coloring-matters form gray-red to grayolive pastes; but when dry they are black powders which are practically insoluble in the usual solvents. They dissolve in sulfuric acid, the solutions being olive brown. WVith reducing agents, such as sodium hydrosulfite in the presence of caustic soda, they give brown vats which dye vegetable ,fiber substantively yielding brown shades which when exposed to the air turn gray.

The coloring-matters obtained from 1. 5 and 1. 8 diamido-anthraquinons yield reddish-gray shades, while those from the 1.3, 2.6, and 2.7 derivatives give greenish-gray shades.

Now what I claim is- 1. As new articles of manufacture, the gray coloring-matters such as can be obtained from diamido anthraquinon bodies, which, when dry, are brown to black powders practically insoluble in water, which give brown solutions with caustic soda and sodium hydrosulfite, which solutions dye cotton brownish shades, which shades become gray when exwhich shades become gray when exposed to I0 posed to the air. the air.

2. Asanew article of manufacture, the gray In testimony whereof I have hereunto set coloring-matter such as can be obtained from my hand in the presence of two subscribing 1.5-d1arn1do-unthraquinon, which, when dry, witnesses.

is a brownish-black powder practically insolu- RENE BOHN. ble in water, which gives a brown solution Witnesses:

with caustic soda and sodium hydrosulfite, ERNEST F. EHRHARDT,

which solution dyes cotton brown Shades, T. ALEO. LLOYD. 

